Influence of anion on the network structure of one dimensional silver(I) coordination polymers of dicompartmental N,N-donor ligands

Three one-dimensional silver(l) coordination polymers {[AgL1]NO3}(n) (1), {[AgL2]ClO4}(n) (2) and {[AgL2]NO3}(n) (2a), where L-1 (pyridin-2-ylmethylene-(4-{[(pyridin-2-ylmethylene)-amino]-methyl}-benzyl)-amine) is a dicompartmental iminopyridine ligand derived from the Schiff-base condensation of alpha,alpha'-diamino-p-xylene and pyridine-2-carboxaldehyde and L-2 (N-(4-((methyl(pyridin-2-ylmethyl)amino)methyl)benzyl)-N-methyl(pyridin-2-yl)methanamine) is the reduced N-methyl derivative of L-1, have been isolated from the reaction of ligands with various silver salts. Six different conformations of L-1 are known that give rise to different network structures for {[AgL1]ClO4}(n). X-ray single crystal structure of polymer 1.5H(2)O reveals that the asymmetric unit contains five water molecules that form a two-dimensional hydrogen bonding network with nitrate counter anion. A new conformer of L-1 is observed in the polymeric structure of 1.5H(2)O. Coordination polymers 2 and 2a, both made of [AgL2](+) repeating unit, contains different conformers of L-2. As a result, different polymeric structures are obtained for 2 and 2a. The effect of counterion on the ligand conformation and subsequently on the polymeric structure is reported. (C) 2012 Elsevier Ltd. All rights reserved.